Rolling mills



nitecl States Patent 3,479,854 ROLLING MILLS Dennis Stubbs, Shefiield, England, assignor to Davy and United Engineering Company, Limited, Sheffield, England Filed May 15, 1967, Ser. No. 643,785 Claims priority, application Great Britain, May 16, 1966, 21,713/ 66 Int. Cl. 1321b 31/30, 31/32, 31/24 US. Cl. 72-244 4 Claims ABSTRACT OF THE DISCLOSURE This disclosure relates to rolling mills and particularly to the means for adjusting the roll gap of a rolling mill. One of the rolls of the mill is adjusted vertically by a pair of wedges arranged between the bearing chock assemblies of the roll and the housings of the mill. One of the wedges of each pair is adjustable longitudinally by a combined piston cylinder assembly screw arrangement, the piston cylinder assembly being connected to and located between the wedges and the screw, in which the screw is employed for coarse adjustment of the wedge and hence the roll and the piston cylinder assembly for a fine adjustment thereof.

It is desirable that the roll gap adjusting means comprises a single unit for each housing, or a single unit on each side of each housing, having a stroke sufiicient to accommodate work roll turndown and a sufiicient speed of response to act quickly in response to an automatic gauge control system. For this purpose in a strip mill the stroke of the roll gap adjusting means should be about 2% inches. The back-up roll wear will be taken care of by packers. A screw operated system generally has a lower speed of response than one operated directly from a hydraulic cylinder, while in a hydraulic operating assembly the stroke of response improves as the size of the cylinder is reduced.

According to the present invention a rolling mill includes an adjustable wedge unit arranged to adjust the roll gap, the wedge unit being actuatable by hydraulic means for fine control, and by screw means for coarse adjustment.

In another aspect the invention provides a rolling mill including an adjustable wedge unit arranged for adjustment of the roll gap, the wedge unit being connected to a hydraulic piston and cylinder assembly for fine control, and the datum position of the hydraulic piston and cylinder assembly being adjustable by further means, preferably a screw, for coarse adjustment. The mill can include means operatively connected to the hydraulic means for controlling roll eccentricity.

In a preferred form the wedge unit has a slidable wedge member connected to an operating rod, which in turn is connected to one member of a piston and cylinder assembly the other member of which is connected to a screw assembly coaxial with the piston and cylinder assembly.

Preferably the wedge is adjustable to vary the roll gap by approximately 2 /2 inches, while the hydraulic cylinder has a stroke only sufiicient to adjust the wedge through only a fraction of this distance for example 0.2 inch. This infers that the cylinder will be sufiiciently small to have a high response speed. The wedge angle should for example be about 1 in 10.

One embodiment of rolling mill adjustment means, in accordance with the invention, will now be described, by way of example only, with reference to the diagrammatic drawing which accompanied the provisional specification and which shows a section through a Wedge adjusting means. In the drawing an adjustable wedge unit 12 is shown positioned in the window 13 of a housing 14 between the housing and a roll bearing chock 15 carrying the neck 16 of a roll 17. The wedge unit 12 comprises an upper wedge member 18 the upper plain surface 20 of which engages the top of the housing window and the lower wedge surface 21 of which engages a corresponding wedge surface 22 of a horizontally slidable wedge member 23. The lower surface of which member 23 is plain and slidable on a plain surface of the lower member 24 of the wedge. A packer 25 is positioned between the lower member 24 and the chock 15. The wedge member 23 is connected to an operating rod 26 the other end of which is connected to a piston 27 slidable in a small volume cylinder 28. Cylinder 28 is connected to a further rod 29 coaxial with rod 26 and having a threaded portion 30. Portion 30 is located in the threaded bore of a nut 31 the exterior of which forms a worm wheel engaging with drive rod 32. The nut 31 is housed in a housing 33 carried by the wedge member 12.

The wedge angle of surfaces 21 and 22 is approximately 1 in 10 allowing vertical wedge adjustment through about 2 /2 inches. The small cylinder 28 allows a vertical wedge adjustment of about 0.2 inch. When further adjustment is required drive rod 32 is driven by a hydraulic or electric motor to rotate nut 31 and thus move rod 29 and cylinder 28 giving a coarse adjustment of the wedge position.

The piston and cylinder assembly 27, 28 is preferably controlled by an automatic gauge control system. The original position of cylinder 28 is set up by the screw assembly and if the piston and cylinder assembly comes to the end of its range during control the piston is arranged automatically to switch in the screw assembly to correct the datum position of the piston and cylinder assembly.

In accordance with the provisions of the patent statutes, 1 have explained the principle and operation of my invention and have illustrated and described what I consider to represent the best embodiment thereof. However, I desire to have it understood that the invention may be practiced otherwise than as specifically illustrated and described.

What is claimed is: 1. A rolling mill comprising: a pair of housings each defining a window, at least two rolls supported at their ends in bearing chock assemblies positioned in said windows,

means at each end of one roll for adjusting the position of that roll with respect to the housings to vary the work roll gap,

said adjusting means comprising a pair of co-acting wedges positioned between the housing and the bearing chock assembly of said one roll, a piston and cylinder assembly having one part thereof rigidly connected to one of said Wedges and the other part connected to screw means whereby the piston and cylinder assembly provides fine adjustment of one wedge relative to the other and said screw means provides coarse adjustment of said one wedge relative to the other.

2. A rolling mill as claimed is claim 1 in which the piston of said piston and cylinder assembly is connected by means of a piston rod to said wedge and the cylinder assembly is connected to said screw means coaxial with said piston rod.

3. A rolling mill as claimed in claim 2 in which said screw is in engagement with a rotatable nut captive in a housing secured to the non-movable wedge and enclosing said piston and cylinder assembly.

4. A rolling mill as claimed in claim 1 in which said screw means is capable of effecting a coarse adjustment over the full range of said wedges,

means for driving said screw means over said full range, and

wherein said piston and cylinder assembly is constructed so that its total stroke effects an additional adjustment of said one wedge of a very small amount in comparison with the full range of adjustment of said one Wedge.

References Cited UNITED STATES PATENTS 3,197,986 8/1965 Freedman, et a1 729 3,355,925 12/1967 Barnikel et a1 72-244 3,369,383 2/1968 Barnikel 7.2 245 CHARLES W. LANHAM, Primary Examiner B. J. MUSTAIKIS, Assistant Examiner U.S. Cl. X.R. 72245, 248 

